Thursday

July 31, 2014

July 31, 2014

Posted by **karen** on Saturday, August 11, 2012 at 5:40am.

1.) A random digit from 1 to 9 (inclusive) is chosen, with all digits being equally likely. The probability that when it's squared it will end with the digit 1.

2.) A random number between 1 and 20 (inclusive) is chosen. The probability that its square root will not be an integer.

- probability -
**MathMate**, Saturday, August 11, 2012 at 7:08am1. Find how many (initial) digits when squared gives one. Dividing that by 9 will give you the required probability.

Also, it may be of interest to note that single digits that add up to 10 have the same last digits when squared.

Example: 2²=4 8²=(10-2)²=64 also ends with the digit 4.

2. Again, determine how many "perfect squares" there are among the numbers 1 to 20. Divide that number by 20 will give you the probability.

**Related Questions**

math - please help! 1.) A random digit from 1 to 9 (inclusive) is chosen, with ...

Math - if the last digit of a weight measurement is equally likely to be any of ...

stats please help test tom - When a computerized generator is used to generate ...

Probability - A group of 90 students is to be split at random into 3 classes of ...

math - your social security number is a 9 digit number. suppose that the last 4 ...

Math - I form a 3-digit number at random from the digits 1-9. What is the ...

Probability - A player is randomly dealt a sequence of 13 cards from a standard...

Statistics - Construct the probability distribution for the value of a 2-card ...

Statistics - Construct the probability distribution for the value of a 2-card ...

stats again please help - When a computerized generator is used to generate ...